Certain known fluid-cooled wind turbines are described in European Patent No. EP 2,136,077; PCT Patent Application No. WO 2010/069954; European Patent No. EP 1525396; Canadian Patent No. CA 2379161; U.S. Published Patent Application No. 2006/0145484; U.S. Published Patent Application No. 2007/103027; European Patent No. EP 1837519 and European Patent No. EP 1586769.
Certain known cooling systems do not always effectively cool the electric machine when it is operated in particularly critical areas.